Service Desk The single point of contact between the service provider and the users. Manages incidents and service requests, and also handles communication with the users.
Incident Management Manages the lifecycle of all incidents. The primary objective is to return the IT service to users as quickly as possible.
Problem Management Manages the lifecycle of all problems. The primary objectives are to prevent incidents from happening, and to minimise the impact of incidents that cannot be prevented.
Change Management Controls the lifecycle of all changes. The objective is to enable beneficial changes to be made with minimum disruption to IT services